The appearance of Bats is always more or less grotesque; but this term more aptly applies to those which live on animal food, in consequence of the additions made to the nose and ears, probably for the sake of increasing their always acute senses of smell and hearing. The ears are frequently of an enormous size, and are joined together at the back of the head; besides which they have leaf, or lance-shaped appendages in front. A membrane of various forms is also often attached to the nose, in one species the shape of a horse-shoe. The bodies are always covered with hair, but the wings consist of a leathery membrane. Another singularity in one genus is the extremity of the spine being converted into two jointed, horny pieces, covered with skin, so as to form a box of two valves, each having an independent motion. The large bats of the East Indies measure five feet from the tip of one wing to that of the other, and they emit a musky odour. The skin of the Nycteris Geoffroyi is very loose upon the body; and the animal draws air through openings in the cheek pouches, head, and back, and swells itself into a little balloon; the openings being closed at pleasure by means of valves. The bite of all is extremely sharp; and we seldom hear of an instance of one being tamed. They try to shelter themselves from chilly winds, and frequent sheltered spots, abounding in masonry, rocks, trees, and small streams. About the Vampire, or the blood-sucker, there are different opinions: that of the East is said to be quite harmless; but it is asserted that the South American species love to attach themselves to all cattle, especially to horses with long manes, because they can cling to the hair while they suck the veins, and keep their victim quiet by flapping their wings over its head; they also fasten themselves upon the tail for the first reason, and a great loss of blood frequently ensues. Fowls are frequently killed by them as they roost upon their perches, for so noiseless and gentle are they in their flight and operations, that animals are not awakened out of their sleep by their attacks. The teeth are so disposed that they make a deep and triple puncture, and one was taken by Mr. Darwin in the act of sucking blood from the neck of a horse. This able naturalist and accurate observer is of opinion, that horses do not suffer from the quantity of blood taken from them by the Vampire, but from the inflammation of the wound which they make, and which is increased if the saddle presses on it. Horses, however, turned out to grass at night, are frequently found the next morning with their necks and haunches covered with blood; and it is known that the bat fills and disgorges itself several times. Dr. Carpenter is of the same opinion as Mr. Darwin, and also disbelieves that these creatures soothe their victims by fanning them with their wings.